Galvanic isolation typically is employed for purposes of isolating circuits powered from different sources. More specifically, two electrical circuits that electrically communicate with each other may have different ground potentials. The isolation prevents ground loops and may protect users of the circuits from potentially hazardous voltages due to the different ground potentials.
One form of galvanic isolation uses magnetic flux coupling, such as the coupling that occurs between primary and secondary windings of a magnetic transformer. Another type of galvanic isolation uses optical coupling that allows otherwise isolated circuits to communicate using light waves. Capacitive coupling may also be used to galvanically isolate two circuits. In this manner, capacitors allow alternating current (AC) to be communicated between the circuits while blocking direct current (DC), thereby allowing the circuits to operate at different ground potentials or from different power sources.